package com.gwh.filter;

import com.alibaba.fastjson.JSON;
import com.gwh.common.BaseContext;
import com.gwh.common.R;
import com.sun.org.apache.bcel.internal.generic.ANEWARRAY;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经登录
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("本次请求为{}",requestURI);
        //定义不需要处理的请求
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        //2.判断本次请求是否需要处理
        boolean flag = check(urls, requestURI);

        //3.如果不需要处理,则直接放行
        if (flag){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1.判断登录状态,如果已经登录,则直接放行
        if (request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录,用户id为{}",request.getSession().getAttribute("employee"));
            Long employeeId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(employeeId);
            filterChain.doFilter(request,response);
            return;
        }
        //4-2.判断登录状态,如果已经登录,则直接放行
        if (request.getSession().getAttribute("user")!=null){
            log.info("用户已登录,用户id为{}",request.getSession().getAttribute("user"));
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request,response);
            return;
        }

        //5.如果未登录则返回未登录结果
           response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    public boolean check(String[] urls, String requestUrl) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestUrl);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
